As I understand it, you want a control panel bypass/over-ride switch that prevents any of the relay modules from triggering. But you only have 12V DC at the control panel.
Assuming the 5V and 12V DC share a common Ground, you could do something like this which does not require an additional relay.
That's good thinking to extrapolate using a 12K (instead of 5K) resistor since you have 12V instead of 5V DC. 12K is kind of an unusual value for the weekend-DIY'er so you might find 10K, 15K, 20K work equally well.
So if the control panel switch is "open", then 12V DC is not supplied to any of the relay modules (only 3 shown above using the miracle of cut-and-paste). So none of the relay modules can trigger whether their respective beams are broken or not.
